Derrick



. Sept. 30, 1941. P. KEMPE DERRICK Filed June 1'7, 1940 P (/1. K E PIPElNVENTOR.

MPa/Lu,

ATTORNEY.

Patented Sept. 30, 1941 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to improvements in derricks, and moreparticularly to an improved derrick of a type used in buildingoperations.

Devices of the type now in use are costly and diflicult to transport. Anobject of the present invention is to provide a device of the type whichwill be light and easy to transport, but which when set up, will bestable enough to handle relatively heavy loads.

Another object of the invention is to provide a sectional derrick whichmaybe quickly and easily assembled or knocked down.

Another object of the invention is to provide a device of the type whichhas a base of relatively light material, which may be loaded to increasethe stability thereof, and which has a sectional boom which may be setup conveniently before the base is loaded.

Other and further objects of the invention will appear as thedescription proceeds, reference being had to the accompanying drawing,in which:

Fig. 1 is a side View in elevation of a derrick embodying my invention.

Fig. 2 is an inverted plan view of the base.

Fig. 3 is a side view of another form of my invention.

Fig. 4 is a side View in elevation of the device before the base hasbeen loaded.

Referring more particularly to the drawing, numeral l refers to thedevice generally, having a base portion H, containing partitionsindicated by dotted lines, l2 and I3. A boom I4 comprises sections l5,l6 and II, which are easily detachable from the base I I, and from eachother. The end section I! contains a sheave, l8, and the base I I hasadjacent its upper end IS the sheave 20. A line 2! is passed aroundsheaves 20 and I8, and terminates in an ordinary handling hook 22.

In the form shown in Fig. 3 the base member 23 has a neck 24 which is soarranged that the boom 25 attached thereto, is exactly vertical. Thisform is especially desirable for use as an elevator in structural work.In the form shown in Fig. l, the boom 14 is shown at an angle of 45.

The base II is divided into compartments by means of the partitions l2and I3, and the end wall 26. Entry into the compartments is made bymeans of the apertures 21 and 28 having the closure plugs 29 and 30. Thepartition l3 enables placement of ballast at a relatively greaterdistance from the curved portion l l, with a resultant increase inleverage during erection of the assembled derrick. The partition l2retains additional ballast within the base 23.

In use, the base member H is transported empty to the scene ofoperations. When unfilled it is relatively light and easily movable. Theoutside arc or bottom of the base H is fiat so that the portion I5 ofthe boom may be connected therewith, and the said base may then betipped upwardly, as shown in Fig. 4, in which position the boom will liehorizontally on the ground or fioor, and additional sections may beattached to lengthen the boom. After the requisite number of sectionshave been attached, the base portion II is gradually filled with oil orsand or other ballast material, whereupon the base will gradually tiltbackwardly toward a horizontal position as it is filled, and inconsequence, will raise the boom to an upright position. It will beunderstood that the free end of boom l4 may be manually lifted off theground as the oil or sand is introduced into the compartments, thuseasily effecting the raising of the derrick by shifting the center ofgravity. The oil or sand may readily be removed by pump or suction meansrespectively. The derrick rope 3| is, of necessity in place before theboom is raised.

In small derricks, the base may be similarly shaped, and of solidconstruction.

It will be understood that the device is capable of many modificationsin structure and design without departing from the spirit of theinvention, within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure byLetters Patent of the United States, is:

l. A derrick comprising a hollow base, a curved end on said base,partition walls within the base, a sectional boom attached to the curvedend of said base whereby whenthe boom is manually lifted to tilt thebase, said base may gradually be filled with weight material to raisethe boom with the curved end as a fulcrum.

2. A device of the character described, including a hollow base havingcompartments therein formed by substantially upright partition walls,the said base having a curved end portion terminating on a plane withthe bottom of said base, a sectional boom detachably secured to thecurved end of said base at an angle thereto with reference to the top ofsaid base, the compartments in said base being adapted for receivingweight ballast for tabilizing the device after the boom is in erectedposition.

PAUL KEMPE.

